Vapor barrier in radiant floor heat
I’ve seen this question asked a few times, but never an answer:
Do you utilize a vapor barrier between radiant floor heated gypcrete and hardwood?
What about an isolation barrier for tile?
And lastly, do you pour your gypcrete directly on the subfloor, or do you lay down 6 mil poly first?
Thanks for any and all help.
Definitely use Ditra between gypcrete and tile. Gypcrete is not a great foundation for tile, even without radiant heat. I'll let someone else answer your other questions.
No poly between gypcrete and subfloor.<!----><!----><!---->
The applicators will spray a sealer/bonding agent first, and then pour the gypcrete.<!----><!---->
It's evaporation rate is very fast and you will be able to walk on the floors in a relatively short period of time.<!----><!---->
You do not need a vapor barrier between the gypcrete and hardwood...a slip sheet yes. DO NOT USE asphalt-impregnated paper as a slip sheet between the hardwood and undersurface (whatever you end up with). USe alternative sleep sheets that won't outgas or leach through to the surface<!----><!---->
I'm guessing you are using sleepers or multilayers of plywood on top of the gypcrete to give you a place to fasten the hardwood.